Normally, protein is not removed when the kidneys filter waste from the blood. However, when the kidneys are damaged, protein leaks through the damaged filters and is removed from the body in the urine, along with the waste products.
1. rucksack-a bag carried by a strap on your back or shoulder. back pack, backpack, haversack, knapsack, packsack. bag-a flexible container with a single opening; he stuffed his laundry into a large bag. kit bag, kitbag-a knapsack (usually for a soldier).ucksack. n. 1. a large bag, usually having two straps and a supporting frame, carried on the back and often used by climbers, campers, etc. US and Canadian name: backpack. [C19: from German, literally: back sack].
Backpacks are measured by the total capacity of all of the pockets in litres, essentially you will be able to fit in 30 litres of gear in a 30 litre backpack. This however might not mean a great deal when you are trying to decide if a rucksack is big or small enough for your needs.